sensor - Can all colors be described with RGB?

If one could pick ideal sensitivities for the RGB filters of a camera sensor, would it be possible to capture any color as humans see it?

Answer

Have a look at this introduction to color perception and reproduction. It also contains a comparison of CIE, RGB and CMYK gamuts at the bottom, where CIE represents what the eye can do and RGB and CMYK what cameras, monitors and printers can do.

In your detailed question, you basically ask, if choosing different RGB filters would accurately model human color perception, which it doesn't:

The human eye is very adaptive, so that cameras for example have difficulties with situations with extreme contrast (where one would use HDR imaging) or low light situations where humans experience a loss of color vision. So it would increase the accuracy or be better model of the set of colors we are able to perceive, but the adapted RGB model would still have limitations.

In addition, being able to accurately model or measure what humans perceive does not solve the problem of creating the same stimulation of color vision in other humans.

That means using a different set of RGB filters will only "cure" the data acquisition of color, but not the reproduction. Your monitor and printer must also be able to reproduce that.

In color reproduction there are other issues present, like 8bit vs 16 and 32bit per channel in sensors, file formats and monitors, calibration of color in output devices, and non-linear perception and adaptivity of your eyes to an extreme range of color and brightness again, for example due to ambient light.

Another issue is that of texture, which can make it difficult to reproduce things like Gold and Silver surfaces correctly.

Please check Poynton's color FAQ.